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THE Wind Power Thread pt 3 (merged)

Discussions of conventional and alternative energy production technologies.

Re: THE Wind Power Thread pt 3 (merged)

Unread postby vtsnowedin » Sun 05 Nov 2017, 13:18:03

GHung wrote:
Show me where they did this for Hoover Dam.
The calculations for Hoover dam were done with a slide rule and if they still are extant they are rolled up in some dusty store room in a BoR archive.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby Newfie » Sun 05 Nov 2017, 13:29:21

VT,
I disagree but let’s save that for a future argument. I think the Spanish team did a good job of explaining it. But for the future. For now, let the first generation stand on their own.

It if they stand on their own then they need to include the full restoration cost.

Is this TRUE life cycle cost included in any of the existing contracts?
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby vtsnowedin » Sun 05 Nov 2017, 13:36:37

Newfie wrote:VT,
I disagree but let’s save that for a future argument. I think the Spanish team did a good job of explaining it. But for the future. For now, let the first generation stand on their own.

It if they stand on their own then they need to include the full restoration cost.

Fine that would give you a good margin of error safety factor.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby coffeeguyzz » Sun 05 Nov 2017, 13:50:03

NWMossback clearly knows his stuff, but why listen to his experienced input if'n it is info one doesn't wish to hear?
Most all the questions regarding turbine maintenance, costs, lifespans, even performance declines, etc,. are easily accessible online if one chooses to do a little research.

Check out the grout problems in the bases of the offshore turbines.
Check out the most recent issues of difficulty in maintaining true vertical in the 50/60 story high newbuilds with such large components that the stress factors are enormous.

The 85 gallons of gearbox oil - supposed to be changed annually prior to the recent adaption of specialized synthetics - took two men 12 hours using a 'bucket brigade' until more innovative processes were adopted. Inadequate change out is suspected for high gearbox failure.

Offshore is INCREDIBLY expensive to maintain and even the operators know it and are determinedly attempting to lower costs.

Offshore US will NEVER - say again NEVER! - take hold as CCGT sourced electricity will be miniscule in cost comparisons.

Studies objectively validating damaging infra sound like the recent Max Planck Institute paper will have lawyers salivating for compensation and insurance companies and financial backers scurrying for cover.

It's over, folks, for US renewables.
This current flurry of wind build out is 100% - say again 100% - prompted by the ITC/PTC programs which will incrementally expire in a couple of years. (Uncle Warren wants to thank you folks for the additional billions he has pocketed through your collective naivety).
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby kublikhan » Sun 05 Nov 2017, 13:53:39

NWMossBack wrote:Wind turbines are maintenance nightmares. After about 15 years the cost of maintaining them is not worth it. There is a new study that just confirmed the results of this one, but I could not find it on line.

http://www.telegraph.co.uk/news/earth/e ... study.html
That study used a statistical model to come up with it's results. A study that looked at actual results from old wind turbines came to a different conclusion:

There has been some debate about whether wind turbines have a more limited shelf-life than other energy technologies. A previous study used a statistical model to estimate that electricity output from wind turbines declines by a third after only ten years of operation.

In a new study, researchers from Imperial College Business School carried out a comprehensive nationwide analysis of the UK fleet of wind turbines. They showed that the turbines will last their full life of about 25 years before they need to be upgraded. The team found that the UK’s earliest turbines, built in the 1990s, are still producing three-quarters of their original output after 19 years of operation, nearly twice the amount previously claimed, and will operate effectively up to 25 years. This is comparable to the performance of gas turbines used in power stations.

The study also found that more recent turbines are performing even better than the earliest models, suggesting they could have a longer lifespan. The team says this makes a strong business case for further investment in the wind farm industry.
New research blows away claims that ageing wind farms are a bad investment
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby KaiserJeep » Sun 05 Nov 2017, 14:09:47

Check out this map to understand WHY the offshore wind resource is where most of the energy can be gathered:

https://www.nrel.gov/gis/images/80m_wind/awstwspd80onoffbigC3-3dpi600.jpg

...it's too big to embed and it needs to be that big to show the level of detail needed.

Note that in the NE, Mid-Atlantic, and the whole right half of the MidWest, where power consumption and populations are concentrated, the wind potential is almost all offshore. My second home on Nantucket Island, for example, is in the average 9.0-9.5 mph average wind speed zone, and the island is about 35 miles offshore.

Note also that there is a lot of potential wind resource in the left half of the MidWest all the way to the Rocky Mountains, a huge area that is sparsely populated. That is available power and should offer lower expenses than offshore - after the buildout of the power grid and storage facilities.

The difference is that we need the power in the NE and every megawatt we collect from wind displaces coal generated power, saving lives and reducing atmospheric carbon injection.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby GHung » Sun 05 Nov 2017, 14:29:43

coffeeguyzz wrote:NWMossback clearly knows his stuff, but why listen to his experienced input if'n it is info one doesn't wish to hear?
.........


The guy who claims to work for a company that has acquired 3 wind energy companies in 7 years, $1.5 billion acquisition this year? That guy? Yeah. The stuff doesn't work so we'll buy it.
No wonder GE is in trouble, eh?

Or maybe they are getting their asses kicked by Vestas and Siemens.

Oh,, Look! A Vestas in Texas.

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Re: THE Wind Power Thread pt 3 (merged)

Unread postby pstarr » Sun 05 Nov 2017, 15:24:21

That pictures speaks a thousand words. Tiny appropriately scaled technology next to a monstrous behemoth. The little windmill runs when there is a breeze, pumps water into long-term essentially free storage. From there it is drawn and used on site to water the livestock. Brilliant! Who thought of that?
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby coffeeguyzz » Sun 05 Nov 2017, 15:44:21

For those of us in the real world, the article "London Array turns two" describes actual operations of the world's largest offshore wind farm.
For comparison purposes, the Lackawanna Energy plant has 1.500 MW capacity, SIX TIMES the functional capacity (630*.4) of the London Array, is fueled by cheap nearby Marcellus gas, can be turned off an on in minutes, and has a staff of 30.
The offshore farm cranks out most prodigiously at night, requires 90 fulltime staff - most working 12 hour shifts - 6 crew boats, is subject to weather conditions, costs TWICE as much to build as Lackawanna, and has 50% rate of maintenance 'unscheduled', aka breakdowns.
NEVER happen in USA
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby ROCKMAN » Sun 05 Nov 2017, 15:59:53

NW - As k said one should assume E.ON has solved that problem. Which is probably why it was one of 8 contracts awarded out of 243 bidders to build one of the first grid storage systems in the UK. A 10 MW design: "At times of either an oversupply or an undersupply, E.ON’s battery system will respond within one second absorbing or discharging power into the local distribution network to which the battery is connected and thus maintaining the system frequency at a safe level."

Doesn't sound like there's an issue with either voltage or any other compatibility requirement.

In fact just discovered the system is up and running as of last Sept...2 months ahead of schedule:

"The project will offer sub-second responses to keep the national grid stable by balancing power supply and demand in real-time to maintain a safe frequency. This is becoming more challenging due to the growing range of renewable generation sources making the electricity system more prone to changes in frequency.

In fact it was designed to specifically deal with the unique nature of renewables:

"The project will offer sub-second responses to keep the national grid stable by balancing power supply and demand in real-time to maintain a safe frequency. This is becoming more challenging due to the growing range of renewable generation sources making the electricity system more prone to changes in frequency."

Still haven't found the cost of the system but:

"Over four years we estimate that this service will save the system operator around £200m (US$262.7 million). This is good news for consumers who benefit from our cost efficiencies, and paves the way for battery technology to establish itself as an important component of our energy system.”

And found this: "Out of a list of some 64 pre-qualified bidders, National Grid picked eight vendors with a combined 201 megawatts of projects, ranging in size between 10 and 49 megawatts apiece, with a total value of £66 million ($86.4 million)."

So if the 10 MW will save about $60 million per year and the 200 MW total projects will cost $86 million then combined projects should payout in less then a year. If they aren't fibbing sounds like a great investment.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby GHung » Sun 05 Nov 2017, 16:03:26

coffeeguyzz wrote:For those of us in the real world, the article "London Array turns two" describes actual operations of the world's largest offshore wind farm.
For comparison purposes, the Lackawanna Energy plant has 1.500 MW capacity, SIX TIMES the functional capacity (630*.4) of the London Array, is fueled by cheap nearby Marcellus gas, can be turned off an on in minutes, and has a staff of 30.
The offshore farm cranks out most prodigiously at night, requires 90 fulltime staff - most working 12 hour shifts - 6 crew boats, is subject to weather conditions, costs TWICE as much to build as Lackawanna, and has 50% rate of maintenance 'unscheduled', aka breakdowns.
NEVER happen in USA


Yes, and I've never been an either-or person. Trains are much more efficient than cars at moving people and goods, but we don't get rid of cars and build more trains everywhere. Wouldn't make sense. If these new combined cycle gas plants are so much more economical and efficient, why aren't they built everywhere?
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby Newfie » Sun 05 Nov 2017, 17:02:09

Been digging around a bit, I’ve got some decent internet for a couple of days for a change

As to the Spanish report: I can’t find the dang thing. The gist is it was written by its two project managers, took a comprehensive look at all the installation and maintenance costs, and laid a format for the Total Life Cycle Analysis. If anyone can find it, I originally came across it here on PO, I would appreciate a link. Or just some search suggestions.

I DID find a number of USA LAND projects are requiring a restoration fund and specifying the restoration measures. The contracts I found were pretty simple documents with no testing or verification measures. Basically they remove the foundation to 4’ below grade and remove roads and add topsoil (of course that’s just moving the site of the damage).
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby Newfie » Sun 05 Nov 2017, 17:05:13

The recent British and EU wind farm reverse auctions have gone for very low numbers. I’m highly skeptical that they are planning on living up to their requirements. I mean what are you gonna do? Once they have the contract and do the build out what do you do if they go belly up? So what if the operator goes bankrupt. You are dependent on the system no matter the cost. It’s a social investment that will require the community to support it. It’s a devils game.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby kublikhan » Sun 05 Nov 2017, 17:40:20

Newfie wrote:I wAs thinking more along the lines of the blades, towers and those zMASSIVE FOUNDATIONS. Or is it just assumed they will be abandoned in place.
What often happens is that the wind farm is upgraded with new turbines as the old turbines age or new technology makes new turbines cost effective for a replacement. This is called repowering and comes in 2 flavors: full repowering and partial repowering. Full repowering is where they take down most of the wind farm: turbines, towers, foundations, but leave the roads, buildings, and transmission lines. Partial repowering is where they leave the foundation and tower intact and simply replace the turbine parts. As for the old equipment, it is sometimes resold in second-hand wind turbine markets such as in Latin America, Eastern Europe, etc where it gets a second lease on life. Otherwise the equipment gets recycled.

Repowering as defined here includes two types of actions. Full repowering refers to the complete dismantling and replacement of turbine equipment at an existing project site. Partial repowering is defined as installing a new drivetrain and rotor on an existing tower and foundation. Partial repowering allows existing wind power projects to be updated with equipment that increases energy production, reduces machine loads, increases grid service capabilities, and improves project reliability at lower cost and with reduced permitting barriers relative to full repowering and greenfield projects. There is also the potential to offset repowering costs by recycling or selling the older equipment.
Wind Power Project Repowering: Financial Feasibility, Decision Drivers, and Supply Chain Effects

GE Renewable Energy today announced at the AWEA Windpower Conference that it has repowered 300 wind turbines, the equivalent of adding 75 wind turbines worth of output. The National Renewable Energy Laboratory has estimated that the U.S. repowering market could grow to $25 billion by 2030. With the largest installed base in the US, GE is uniquely positioned to serve this growing market segment.

As the US wind industry matures, legacy units are old enough to benefit from this lifecycle extension program, which brings new value to wind farm customers through upgrades and technology advancements.
Anne McEntee, GE Renewable Energy Vice President and Services CEO said “The Repower program can include increasing a turbine’s rotor size, and upgrades to the gearbox, hub, main shaft, and main bearing assembly. This is an exciting opportunity to bring new life to older turbines and help them provide even more energy for years to come. Repowering is so much more than simply providing new wind turbine equipment—we’re bringing the entirety of GE to the table for our customers, providing options for servicing, grid solutions, forecasting and tailored financing solutions.” “The GE repower package provides the opportunity to modernize our windfarms, improving the efficiency and increasing the farm output. Repowering ensures our wind turbines not just remain productive, but perform better than ever.”
GE Adds Value to the US Wind Turbine Industry With its Repower Offering
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby kublikhan » Sun 05 Nov 2017, 17:59:50

Newfie wrote:Been digging around a bit, I’ve got some decent internet for a couple of days for a change

As to the Spanish report: I can’t find the dang thing. The gist is it was written by its two project managers, took a comprehensive look at all the installation and maintenance costs, and laid a format for the Total Life Cycle Analysis. If anyone can find it, I originally came across it here on PO, I would appreciate a link. Or just some search suggestions.
Was it one of these papers:

Life cycle assessment of a multi-megawatt wind turbine

LCA sensitivity analysis of a multi-megawatt wind turbine

Those papers are a bit old though and one of them is behind a paywall. This one is a bit more recent:

Abstract: Wind turbines produce energy with virtually no emissions, however, there are environmental impacts associated with their manufacture, installation, and end of life. The work presented examines life cycle environmental impacts of two 2.0 MW wind turbines. Manufacturing, transport, installation, maintenance, and end of life have been considered for both models and are compared using the ReCiPe 2008 impact assessment method. In addition, energy payback analysis was conducted based on the cumulative energy demand and the energy produced by the wind turbines over 20 years. Life cycle assessment revealed that environmental impacts are concentrated in the manufacturing stage, which accounts for 78% of impacts. The energy payback period for the two turbine models are found to be 5.2 and 6.4 months, respectively.

Conclusions
This LCA study compared the environmental impacts of two 2.0 MW wind turbines using two methods (ReCiPe 2008 and energy payback). The tower, rotor, and nacelle are found to have the greatest contribution to the environmental impact in each case. For the tower, the large amount of steel required is the major contributor to cradle-to-grave environmental impact. One of the outcomes from this LCA study is the confirmation that the main life cycle environmental impacts of a wind turbine originate from the manufacturing stage. When compared to prior work, the results lead to a similar conclusion that environmental impacts are driven by the material consumption, especially steel.
It was shown that the use stage has an almost negligible environmental impact due to maintenance activities. In addition, the transportation distances of wind turbine components to the wind park site influenced environmental impact. The travel distance of model 1 is longer than model 2 by 16,000 km (approximately 50%), and some components for model 1 are transported from other continents. It was found that recycling is important to the environmental profile of the turbine, while transportation type can have a profound effect on life cycle impacts when components must travel relatively longer distances.
Comparative life cycle assessment of 2.0 MW wind turbines
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby vtsnowedin » Sun 05 Nov 2017, 18:00:57

If you wanted to take a shallow water turbine totally out of service removing the foundation all the way to the sea floor might not be the best option. Demolishing it down to an elevation well below the draft of any possible ship that might pass by and leaving the concrete rubble where it falls around the stub of the base would provide an artificial reef where the nooks and crannies between the fallen chunks would make excellent lobster condominiums.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby coffeeguyzz » Sun 05 Nov 2017, 18:35:51

Ghung

That is a timely question for several reasons.
The biggest reason is the need for adequate natgas supply, and - consequently - the ferocious opposition to pipeline build out by renewable advocates.
However, the build out IS proceeding with many delays.
Two large pipelines are targeting the US southeast - Atlantic Coast Pipeline and Mountain Valley.
Once these are built (expected within 24 months), there will be future expansion potential which is much easier to accomplish.
There are already several CCGT plants being built or planned in the south east, and 26 in Ohio and Pennsylvania alone.
It's kind of a shame that anti fossil fuel folks have so thoroughly demonized natgas as the systems work most effectively with intermittent (think wind) supply.

VTS, trawling fishing boats are not compatible with remnant, sea-bottom structures.
This aspect is a very strong influence against offshore turbines in the northeast US.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby GHung » Sun 05 Nov 2017, 19:30:12

coffeeguyzz wrote:Ghung

That is a timely question for several reasons.
The biggest reason is the need for adequate natgas supply, and - consequently - the ferocious opposition to pipeline build out by renewable advocates.
However, the build out IS proceeding with many delays.
Two large pipelines are targeting the US southeast - Atlantic Coast Pipeline and Mountain Valley.
Once these are built (expected within 24 months), there will be future expansion potential which is much easier to accomplish.
There are already several CCGT plants being built or planned in the south east, and 26 in Ohio and Pennsylvania alone.
It's kind of a shame that anti fossil fuel folks have so thoroughly demonized natgas as the systems work most effectively with intermittent (think wind) supply.

VTS, trawling fishing boats are not compatible with remnant, sea-bottom structures.
This aspect is a very strong influence against offshore turbines in the northeast US
.


Which is why sport fishing around these structures is generally good.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby vtsnowedin » Sun 05 Nov 2017, 19:41:26

GHung wrote:
coffeeguyzz wrote:Ghung

That is a timely question for several reasons.
The biggest reason is the need for adequate natgas supply, and - consequently - the ferocious opposition to pipeline build out by renewable advocates.
However, the build out IS proceeding with many delays.
Two large pipelines are targeting the US southeast - Atlantic Coast Pipeline and Mountain Valley.
Once these are built (expected within 24 months), there will be future expansion potential which is much easier to accomplish.
There are already several CCGT plants being built or planned in the south east, and 26 in Ohio and Pennsylvania alone.
It's kind of a shame that anti fossil fuel folks have so thoroughly demonized natgas as the systems work most effectively with intermittent (think wind) supply.

VTS, trawling fishing boats are not compatible with remnant, sea-bottom structures.
This aspect is a very strong influence against offshore turbines in the northeast US
.


Which is why sport fishing around these structures is generally good.

Yes!! My limited deep sea fishing experience (about one trip a summer) has shown me that a wreck or other obstacle keeps the dragers from plowing the sea bottom into a sterile desert to keep from losing nets and other gear. Drifting a jig above a cannon ball sinker (so as not to get caught on old nets) will often put a good fish onto every line as you drift by.
If I had my way I'd buy out every drager and sink their boats into a well planned artificial reef.They have fished the New England coast almost completely dry and need to take a five to ten year rest to let the stock recover.
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Re: THE Wind Power Thread pt 3 (merged)

Unread postby NWMossBack » Sun 05 Nov 2017, 22:17:11

ROCKMAN wrote:Doesn't sound like there's an issue with either voltage or any other compatibility requirement.


Rock - I said wind and solar PV do not currently provide significant voltage and frequency support, and batteries do not _necessarily_ solve that problem. As I also said, those features could be engineered into the inverter, but that added complexity is not included in EROEI calculations for wind & solar. I have not seen any analysis of the EROEI impact of adding batteries to wind, but at a starting point of only 5:1 it would not take much to push it into unprofitable territory. (I think 3:1 is right around the economic break point.) Also I said that the grid is designed around very large _inherently stable_ rotating machines, which _currently_ limits solar and wind penetration to around 10 to 15% to maintain stability. I am sure that number will be improved upon, and I think batteries are worth looking into, but as I already said that technology is unproven at the scale that would be required for a wholesale switch to an all renewable grid, and much more work is required before anyone can say it definitely is or is not possible. Remember that we would be replacing inherently stable generators with inherently unstable ones that require a long series of energy conversions, sophisticated computers, and very large semi-conductors. For an analogy think of an airplane; would you rather be a passenger on an inherently stable plane that does not need computers and would stay in the air even if the pilot took a little nap, or an inherently unstable plane that needs hundreds of decisions a second by a computer sent to the control surfaces, with hundreds of things that could go wrong every second. The question should not be just what is technically possible, it should also be what is more robust, what is economically feasible, what carries more benefits than drawbacks, etc.
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